Semiconductor device and method of manufacturing the same

A method of manufacturing a semiconductor device, comprising:

• providing a device intermediate comprising a semiconductor substrate of a first general conductivity type, a semiconductor layer of the first general conductivity type disposed on the semiconductor substrate and a first insulating film disposed on the semiconductor layer;
• forming a gate electrode on the first insulating film;
• forming an impurity region of the first general conductivity type in the semiconductor layer under the gate electrode after the formation of the gate electrode;
• forming two channel regions of a second general conductivity type in the semiconductor layer so that the impurity region connects the two channel regions;
• forming a source region of the first general conductivity type in each of the channel regions;
• and
• forming a second insulating film covering the gate electrode.

A method of manufacturing a semiconductor device, comprising:

• providing a device intermediate comprising a semiconductor substrate of a first general conductivity type, a semiconductor layer of the first general conductivity type disposed on a surface of the semiconductor substrate and a first insulating film disposed on the semiconductor layer;
• forming on the first insulation film a gate electrode having an opening therein;
• implanting a first impurity for the first general conductivity type into part of the semiconductor layer through the opening of the gate electrode;
• implanting a second impurity for the second general conductivity type into part of the semiconductor layer that is outside the gate electrode;
• heating the device intermediate so that the first and second impurities are diffused so as to form an impurity region and a channel region that have an junction interface perpendicular to the surface of the semiconductor substrate;
• forming a source region of the first general conductivity type in the channel region;
• and
• forming a second insulating film covering the gate electrode.

A semiconductor device comprising:

• a semiconductor substrate of a first general conductivity type;
• a semiconductor layer of the first general conductivity type disposed on a surface of the semiconductor substrate so as to provide a drain region;
• two channel regions of a second general conductivity type disposed on the semiconductor layer;
• an impurity region of the first general conductivity type disposed between the two channel regions so as to connect the two channel regions;
• an insulating film disposed on the impurity region;
• a gate electrode disposed on the insulating film and comprising a first gate electrode portion and a second gate electrode portion that are disposed on the impurity region between the two channel regions, the first gate electrode portion being at least partially separated from the second gate electrode portion;
• and
• a source region of the first general conductivity type formed in a surface of each of the channel regions.

A semiconductor device comprising:

• a semiconductor substrate of a first general conductivity type;
• a semiconductor layer of the first general conductivity type disposed on a surface of the semiconductor substrate so as to provide a drain region;
• two channel regions of a second general conductivity type disposed on the semiconductor layer, each of the channel regions being elongated in a direction;
• an impurity region of the first general conductivity type disposed between the two elongated channel regions, the impurity region being elongated in the direction;
• an insulating film disposed on the elongated impurity region and channel regions;
• a gate electrode disposed on the insulating film and having a slit elongated in the direction but not reaching an edge portion of the gate electrode;
• and
• a source region of the first general conductivity type formed in a surface of each of the channel regions.